A family of Microsoft word processing software products for creating web, email, and print documents.
You can easily add the following to your QAT.
The E-Mail as PDF Attachment creates the pdf and attaches it to an email ready to be addressed and sent. It uses the default email program.
You want to choose commands from under the File Tab. The command/menu is Send.
If you want you can save the QAT modification in a document or template rather than in the default on your computer. This will mean it would be available for anyone using the template even if not on your computer. See step (6) in the screenshot.
Modifying the Quick Access Toolbar (QAT) in Microsoft Word
Note: The default text for that button is Send but you could change it to Send E-Mail if you want.
I assume that by button, you meant an ActiveX button which requires macros. This does not require any macro and would not have to be saved in a .docm/.dotm file. It likely will also work on a Mac while ActiveX would not.